Shear strengthening of brick masonry walls with opening

In this study, results of testing eight clay brick walls are presented. The walls were tested under distributed vertical load and gradually increased lateral load. The walls consisted of one solid wall, two walls as control and five walls with openings strengthened by using: RC frame around the opening, RC frame with the lintel extended to the ends of the wall, steel channel frame around the opening, confining the wall with RC frame, and near-surface mounted bars. Results showed that all the strengthening techniques increased lateral load-carrying capacity, ductility and toughness compared to the non-strengthened walls. The highest increase in shear strength was for the wall strengthened with steel frame around the opening 88%, followed by the wall strengthened with NSM steel bars 56%. From the load deflection curves energy dissipated by the walls during loading was calculated. Walls with interior steel frame, outside confinement, interior RC frame showed the highest increase in energy dissipation over the control wall by 470, 268, and 250% respectively. Calculation of shear strength based on existing equations is presented, and an analytical model is proposed for predicting lateral shear strength of walls with opening. The results show fair agreement with test results.